WhatsApp CEO, Co-Founder Jan Koum Says He's Leaving Facebook

(Bloomberg) -- WhatsApp founder and Chief Executive Officer Jan Koum is leaving Facebook Inc., just a few years after his messaging app was acquired by the social-media giant for $22 billion.

With Koums departure, Facebook loses one of its staunchest internal advocates for user privacy, amid a broader crisis of trust over Facebooks treatment of personal data. Koum posted his plan to depart on his Facebook page, saying the decision was emotional. His mobile-messaging tool, which has been kept separate from Facebooks main social network, its Messenger app and other businesses, is known for offering end-to-end encryption, meaning only the sender and recipient can see the content of messages. The app has about 1.5 billion users worldwide. The news received a quick response from Facebook CEO Mark Zuckerberg.

“Im grateful for everything youve done to help connect the world, and for everything youve taught me, including about encryption and its ability to take power from centralized systems and put it back in peoples hands,” Zuckerberg wrote. “Those values will always be at the heart of WhatsApp.”

The Washington Post reported earlier that Koum is exiting the company after clashing with Facebook over strategy, and that he also plans to leave Facebooks board. The other co-founder of WhatsApp, Brian Acton, also left recently -- and last month posted the #DeleteFacebook hashtag during the social networks scandal over user privacy.

When asked who will replace Koum at the head of WhatsApp, or whether he plans to remain on Facebooks board, the company said it had no comment. The company also declined to comment on whether Facebook plans to start advertising on WhatsApp — a business model the founders promised they would never use.

Facebooks purchase of WhatsApp in 2014 was quick and expensive, at a time when Zuckerberg was racing to expand the companys reach on mobile devices. Koum is the only executive to have been given a board seat as part of a Facebook acquisition. It was unclear at the time how the social network might implement its business model -- based on gathering user data to better target advertisements -- at WhatsApp, and there was a clash of cultures from the beginning. Koum and Acton remained committed to privacy and encryption, while Facebook needed to find a way to make money from the app.

WhatsApps strict encryption helps Facebook serve an audience that cares deeply about privacy, but it has gotten the company into other kinds of legal trouble. Facebook has been frequently sued around the world for records related to potentially criminal conversations on WhatsApp, which the company says it cant access because of the apps encryption.

Koum didnt elaborate on his reasons for leaving aside from saying in his statement that its time for him to move on after almost a decade. “Im taking some time off to do things I enjoy outside of technology, such as collecting rare air-cooled Porsches, working on my cars and playing ultimate frisbee,” Koum wrote. “And Ill still be cheering WhatsApp on – just from the outside.”

--With assistance from Nathan Crooks .

To contact the reporter on this story: Sarah Frier in San Francisco at sfrier1@bloomberg.net.

To contact the editors responsible for this story: Jillian Ward at jward56@bloomberg.net, Andrew Pollack